Year : 2021 Month : June Volume : 10 Issue : 23 Page : 1809-1814

Parathyroid Adenoma - From Surgical to Biochemical Cure

Rupa Mehta1, Nitin M. Nagarkar2, Satish S.S.3, Ripu Daman Arora4, Jyoti Ranjan Das5

1, 2, 3, 4, 5 Department of ENT & Head Neck Surgery, All India Institute of Medical Sciences, Raipur (AIIMS), Chhattisgarh, India.

CORRESPONDING AUTHOR

Dr. Jyoti Ranjan Das, Department of ENT & Head Neck Surgery, All India Institute of Medical Sciences, Raipur (AIIMS), Chhattisgarh, India.
Email : jdbegins007@gmail.com

INTRODUCTION

Parathyroid glands, minute endocrine glands, located in posterior aspect of thyroid glands secrete parathormone which plays an important role in maintaining calcium homeostasis in the body. The superior and inferior parathyroid glands originate from the 4th and 3rd branchial pouches respectively and migrate to occupy their normal positions in relation to the thyroid gland.1 Hyperparathyroidism is defined as hyper functioning of parathyroid gland and can be primary, secondary or tertiary. Primary hyperparathyroidism is due to parathyroid gland proliferative disorders which include parathyroid adenoma, parathyroid hyperplasia, parathyroid carcinoma or in association with other conditions in MEN syndrome. In more than 90 % patients,  primary hyperparathyroidism is caused by a single parathyroid adenoma. Very rarely double parathyroid adenomas are seen. Secondary Hyperparathyroidism is caused in response to any chronic hypocalcaemic conditions like renal failure, gastrointestinal malabsorption, dietary rickets & drugs, like phenytoin, phenobarbital & laxative. Prolonged secondary hyperparathyroidism leads to tertiary hyperparathyroidism due to autonomous secretion.

The clinical presentation of hyperparathyroidism is classically described as kidney stones, abdominal groans, painful bones, psychic moans, and fatigue overtones. In the initial course of the disease, the patients present with vague symptoms of fatigue, muscle and joint pain, frequent urination, nausea, constipation, and decreased appetite. If high index of suspicion is maintained, they can be conveniently diagnosed by routine blood tests which show increased calcium levels. However, in India still majority of people are diagnosed when they present with palpable neck mass, skeletal manifestations or deranged renal function.

We hereby present 5 cases of parathyroid adenoma managed at our centre over a period of 2 years.

PRESENTATION OF CASE

Case 1

A 48-year-old female presented with accidental fracture of left humerus after trivial injury. She presented to Orthopaedics outpatient department where she underwent closed reduction of fracture and cast was applied. X-Ray humerus (Figure 1) was suggestive of diffuse osteopenia with multiple well defined lytic lesions seen in left humerus at upper and mid shaft with pencil thin cortex.

She gave a history of joint pain and muscle weakness. She didn’t have any history of body weight loss or loss of appetite. She denied having any neck swelling or dysphagia or change of voice. There was no past history suggestive of any chronic disease.

During workup she was found to be hypercalcaemic. Serum calcium level was 14.9 mg / dl (normal 9 to 11 mg / dl), serum phosphorus level was 2.4 mg / dl (normal 2 to 4.5 mg / dl. Subsequently parathyroid hormone level was tested which was raised - 1900 pg / ml (normal 14 to 71 pg / ml), Alkaline Phosphatase level - 897 IU (normal 33 to 105 IU) serum magnesium 1.5 mg / dl (normal 1.7 to 2.4 mg / dl), 25 - OH vit D was 12.08 ng / dl (normal 20 to 50 ng / dl). Thyroid profile was normal. Other investigations revealed normal complete blood count and renal parameters.

     On detailed clinical examination, we found a single small 2 cm firm, non-tender, swelling over anterior aspect of neck just right side of midline just below the level of thyroid cartilage. Swelling was moving with deglutition. Ultrasonography of the neck revealed a well-defined hyper echoic lesion measuring 3 X 3.3 X 4.4 cm seen in relation to lower pole of the right lobe of thyroid at posterior aspect. Lesion showed moderate vascularity within. It was consistent with right Parathyroid Adenoma. CECT Neck (Figure 1) was suggestive of large mass located posteroinferior to the right lobe of thyroid, mostly, parathyroid neoplasia. Tc99 sestamibi scintigraphy revealed an area of increased uptake in lower pole of right thyroid with retention of tracer in the delayed images which was suggestive of right inferior parathyroid adenoma.

Diagnosis of primary hyperparathyroidism due to right inferior parathyroid adenoma was made and surgical excision was planned. Right inferior Parathyroidectomy was done to remove right inferior parathyroid adenoma. Parathormone assay 10 mins after excision of the gland showed substantial drop in parathormone levels to 120 pg / ml. Histopathological examination showed abnormal parathyroid consistent with parathyroid adenoma. Postoperatively, the patient showed evidence of hungry bone syndrome with symptomatic hypocalcaemia. She was managed with calcium and Vit D3 supplement. On follow up, her serum calcium levels declined to normal levels (Table 1). Serum intact PTH level on 2nd month follow up was 66 pg / ml (Table 1). After one-year  post-op follow up patient was normal and there was no recurrence.

 

 

Case 2

A 44-year-old lady presented with recurrent swelling over right maxillary region since 2 - 3 years with history of surgery for similar swelling before, On histopathological examination (HPE), it was diagnosed as giant cell tumour of upper jaw. There was no history of recurrent fracture, bone pain, abdominal pain and urinary complaints. There was no significant personal and family history. On clinical evaluation of right maxillary region, a diffuse bony hard swelling was palpable. Patient was advised CT scan from the base of skull to clavicle which showed a heterogeneously enhancing solid cystic mass at right side of neck, posterolateral to the right lobe of thyroid, possibility of parathyroid adenoma (Figure 2). Chest X-ray and USG abdomen were within normal limits.

On biochemical evaluation she was found to be hyper calcaemic and serum parathyroid hormone level was also raised. Serum calcium level was 13.1 mg / dl (9 - 11mg / dl), serum parathyroid level was 782.1 ng / ml (14 - 71ng / ml), alkaline phosphatase level - 387 IU (33 - 105 IU). Serum vitamin D, magnesium and phosphorus levels were normal. Thyroid profile was also normal.

Technetium 99 sestamibi scintigraphy (Figure 2) scan revealed scintigraphic evidence of high probability of hyper functioning of right inferior parathyroid adenoma with high metabolic turnover rate. USG guided FNAC was suggestive of right parathyroid swelling consistent with parathyroid lesion.                 On the basis of all these investigations diagnosis of right inferior parathyroid adenoma was made and the patient was planned for surgical excision. Right inferior parathyroidectomy was done along with right maxillary region and giant cell tumour curettage via lateral rhinotomy approach. Histopathological examination confirmed parathyroid adenoma. Parathormone assay 10 min after excision of the gland showed substantial drop in parathormone levels to 90 pg / ml. Postoperatively calcium and vitamin D supplementation had to be given to tide over hungry bone syndrome. On regular follow up at 3 months, serum intact PTH level was 64 pg / ml and serum calcium level was also normal (Table 2).

 

 

Case 3

A 13-year-old boy presented in orthopaedics outpatient department for bowing of leg deformity. He was having bone pain since 6 months. He had Genu valgum with pectus excavatum (Figure 3). On examination there was small cystic firm swelling palpable on anterior aspect of the neck just right side of midline at thyroid level. He was evaluated thoroughly and found to be hyper calcaemic (sr calcium: 17.7 mg / dl), serum parathyroid hormone (sr PTH: 1254.8 pg / ml) and Serum alkaline phosphatase level (sr. ALP: 2350 U / L) were also raised. Serum Vit D, magnesium and phosphorus levels were normal. 24 hours urine calcium was (504 mg / 24 hrs). Thyroid profile was normal.

X ray of both legs showed bilateral Genu Valgum with decreased bone density with prominent trabeculations & thinning of cortices. Margins of metaphysis appeared irregular in all visualized bones (Figure 4). USG neck showed heteroechoic mass measuring 3.8 * 2.2 cm seen in right inferior parathyroid region with increased vascularity suggestive of right inferior parathyroid mass. USG guided FNAC from right inferior parathyroid mass suggestive of parathyroid neoplasm.

Patient was planned for right inferior parathyroidectomy. During surgery right side inferior parathyroid gland was found to be enlarged up to 3 cm * 4 cm. Rest all three parathyroid glands were normal on palpation and consistency. So right inferior parathyroid was excised with confirmed parathyroid adenoma histopathologically. Immediately post-operative serum PTH level dropped down to 89 pg / ml and sr calcium

level to 10.1 mg / dl. During postoperative period patient developed hungry bone syndrome and required calcium and vitamin D supplementation. Bone pain reduced substantially.

 

 

Serum PTH and Serum calcium level came to normal (Table 3). However alkaline phosphatase levels were fluctuating, and the bow leg deformity had not improved. Orthopaedicians have advised correction of the deformity once the alkaline phosphatase levels stabilize.